Datasheet
Package Availability, Models, Samples & Pricing
General Description
LP3944 is an integrated device capable of independently driving 8 LEDs. This device also contains an internal precision oscillator that provides all the necessary timing required for driving each LED. Two prescaler registers along with two PWM registers provide a versatile duty cycle control. The LP3944 contains the ability to dim LEDs in SMBUS/I2C applications where it is required to cut down on bus traffic.
Traditionally, to dim LEDs using a serial shift register such as 74LS594/5 would require a large amount of traffic to be on the serial bus. LP3944 instead requires only the setup of the frequency and duty cycle for each output pin. From then on, only a single command from the host is required to turn each individual open drain output ON, OFF, or to cycle a programmed frequency and duty cycle. Maximum output sink current is 25 mA per pin and 200 mA per package. Any ports not used for controlling the LEDs can be used for general purpose input/output expansion.
Reliability Metrics
| Part Number |
Process |
EFR Reject |
EFR Sample Size |
PPM * |
LTA Rejects |
LTA Device Hours |
FITS |
MTTF (Hours) |
|
LP3944ISQ | CMOS7 | 0 | 13906 | 0 | 0 | 862500 | 5 | 244736730
|
|
LP3944ISQX | CMOS7 | 0 | 13906 | 0 | 0 | 862500 | 5 | 244736730
|
Note: The Early Failure Rates were calculated as point estimates. The Long Term Failure Rates were calculated
at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress
temperature of 150°C to an application temperature of 55°C.
For more information on Reliability Metrics, please click here.
Application Notes
| Title | Size in Kbytes |
Date |
 |
| AN-1344: Application Note 1344 LP3944 Evaluation Kit |
366 Kbytes |
20-Oct-04 |
Download |
| AN-1715: Application Note 1715 LP3943/LP3944 as a GPIO Expander |
93 Kbytes |
12-Oct-07 |
Download |
AN-1715 (Chinese): Application Note 1715 LP3943/LP3944 as a GPIO Expander
|
252 Kbytes |
|
 |
More Application Notes
| Title | Size in Kbytes |
Date |
|
| AN-1296: Application Note 1296 LP3945/LP3946 Evaluation Kit |
280 Kbytes |
17-Sep-04 |
Download |
| AN-1300: Application Note 1300 LP3943 Evaluation Kit |
466 Kbytes |
20-Oct-04 |
Download |
| AN-1341: Application Note 1341 LP3947 Evaluation Board |
584 Kbytes |
18-Nov-04 |
Download |
[Information as of 21-Nov-2008]
|
RoHS Compliance Information
